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Difference between revisions of "DEP"

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<b>D</b>ata <b>E</b>xecution <b>P</b>revention.
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<b>D</b>ata <b>E</b>xecution <b>P</b>revention is a hardware-layer feature provided by modern [[instruction set architecture]]s.  On Intel CPU's, this is called the '''NX bit''', and on AMD CPU's, this is called the '''XD bit'''.  These bits provide the [[assembly]] instructions '''jno''' and '''jo''', ''jump if no overflow'' and ''jump if overflow'', respectively.
  
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Microsoft's Windows XP SP2 Operating System was Microsoft's first real attempt at data execution prevention. While the attempt was in fact a feeble one, it laid the ground work for later innovations, for example [[ASLR]], or [[ASLR|Address Space Layout Randomization]] employed by Microsoft's Windows Vista Operating System.
 
Microsoft's Windows XP SP2 Operating System was Microsoft's first real attempt at data execution prevention. While the attempt was in fact a feeble one, it laid the ground work for later innovations, for example [[ASLR]], or [[ASLR|Address Space Layout Randomization]] employed by Microsoft's Windows Vista Operating System.
  
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{{countermeasures}}
 
{{countermeasures}}
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Latest revision as of 04:40, 19 November 2012

Data Execution Prevention is a hardware-layer feature provided by modern instruction set architectures. On Intel CPU's, this is called the NX bit, and on AMD CPU's, this is called the XD bit. These bits provide the assembly instructions jno and jo, jump if no overflow and jump if overflow, respectively.